My Own Vintage JBL Studio Montors?

SX88POWER, does your school have a woodworking shop class where you can learn to read a tape measure, cut, and assemble speaker enclosures without cutting your fingers off? Everything else you need to learn about building speakers can be found online these days. As has been stated, wood working tools are not cheap and you need a garage sized space to use it all in. I would find a job in a CNC cabinet shop for a summer job and you will be well on your way to realizing your dream.

You might also want to investigate 2 year trade schools specializing in the cabinet trade. Or get that civil, mechanical, or electrical engineering degree and be able to afford to just finance your own wood shop yourself. :)

Nice Volvo 244, good choice of car. :)
 
VolvoHeretic said:
....and you need a garage sized space to use it all in.
:)
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LOL.. I forgot about mentioning that too.... The OP don't wanna know what I spent last year just on just materials to build my shop, and it took me almost 4 months of solid working to get it built by myself.

Let's just say for what that building cost me, I could have bought some of the most insane JBL speakers you could imagine... I could have bought at least 2 Paragons...
 
My $.02

If you don't use JBL drivers, you'll have to design your own crossovers. For something like a 4-way monitor, this will be a much more daunting task than building the box. Somebody will post a link to a Westend article that shows how to build a second order filter or something to illustrate that it's no big deal, but successful integration of a multi-way crossover is anything but simple. Take a look at some of the 4-way JBL crossovers and compare to the bare filter to get an idea of how much more work, measurement, measurement equipment, etc. is required.

It's a lot of work for people who have years or decades of experience. Building a really nice box, what you see as the challenge, is not that big of a deal in comparison.

Just make it active, some will say. That's fine for a few enthusiasts, but most people just want to hook the speakers up and play.

Just another perspective.
 
The heart of the JBL speakers are the drivers and the crossover, not the box.

Without the drivers, it's just a homebrew speaker that sort of looks like a classic JBL design

The box, if properly constructed, means nothing (unless it's a JBL original).
 
bhunter said:
These folks still do :
http://www.cathedralspeakers.com/

Klipsch still has their Heritage line and their very large Jubilees are available IIRC. Wilson and Magico both make large speakers.

There's a reason there are not a lot of large speakers currently being manufactured; namely, lack of anything more than a niche market. IMO, there is plenty of competition within that niche market.

Kenrick has a unique position that IMO can not be replicated outside of the audio fanaticism of Asia.
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Of course most of you guys knew that i meant not necessarily Dunlavy SC-VI size AUDIOPHILE, out of price systems.
Of course, there are large speaker systems available, most out of price, but for Joe-Average wanting something big, with big realistic
bass, hummm...
I'm not sure that we really need 4 way systems either, except for PA of large venues. A good implemented and x-overed 3 way does
the job well.
 
Hey guys,

Yeah I get what you are all saying, I think I may need to reconsider just how feasible all of this is as my funds are pretty limited. For now, I might try to build and build something smaller and see how it goes. Im good friends with a mechanic down the street who I might ask about a part time job soon, so i've got backups haha. I thank all of you for your input, as its good to hear from the experts. Ill be sure to report back when I make up my mind or something happens.

Best regards,

-Johannes
 
Yes, regarding the tools, I don't have a CNC shop at my fingertips lol, but I do have a fair amount of higher end woodworking tools that I inherited from my grandfather who was a carpenter. I also have an entire garage that I could dedicate to this. In terms of crossovers, I was just going to use a 250hz low pass for the woofer, and then a two way crossover for the mid and highs with a restricting capacitor to the super-tweeter. This would make the speakers bi-ampable for the best flexibility. I did all of the research to ensure that the impedances of the drives would match, so that the crossover frequencies would not change and would be dead on. However, I'm definitely going to try and pursue something smaller to start. Perhaps just a clever little bookshelf monitor which would be more marketable and easy to build. Hey thanks for the compliment Volvo Heretic, that 244 is not actually my car, but I have an '88 240 wagon in gold which I think you would approve of:rflmao:. Its rolling four mint Virgo rims thanks to my personal friend on here Audiojones, and full new IPD suspension hopefully by next week once I finish bolting it all on.

Thanks again,

-Johann
 
Ahhhhhhh :no:, ''clever lil bookshelf monitors'' can be found at the drug store, everywhere, including trash cans ;)...
Don't go into that :beatnik:.
 
Hehe, yeah I know, I'm a junkie for huge speakers too. :D My first ever pair were a set of mint Pioneer CS-63DXs which I still use daily.
 
The one niche I can sort of see is building replica JBL cabinets for the ones that tend to fall apart, L100, L65, 4311, etc. I often wonder - if the cabinets were replaceable, would people be more apt to keep using their components instead of parting them out when the cabs suffer water damage or otherwise break?
 
To be perfectly honest, I don't think that you'll make enough money to support yourself building speakers unless you already have an established base of clientele. The equipment and/or knowledge to engineer a speaker system that sounds uniform over most of the frequency range from disparate drivers is quite expensive, or takes some serious time and listening to acquire. I'm 24, and have been messing with this stuff seriously for the last decade and less seriously since I was 3. I'm not going to try and make audio my daily living-I just have to work too hard for not enough return. It's a fairly lucrative side gig (live theatre mixing, corporate AV, transers, system setup, etc).

Only now I do start to trust myself to engineer decent response out of home made Frankenspeakers using active crossovers and a nice stack of power amps. To start on your speaker journey, I would look into getting a pair of 5 channel amplifiers from a home theater setup, or one of those whole house 60wpc amplifiers, and a Behringer DCX2496 crossover or two. Then, get some decent drivers and start experimenting with the sounds of different crossover slopes, EQ, phase inversion, time alignment, and all the other fun things that go along with it. If you can get good sound out of a set of frankenspeakers using a crossover that can be cloned cheaply, then you might consider making a couple pairs to try and sell.

Feel free to ask me any questions you may have!
 
Hey David.. Cool to see you.. I was wondering the other day if you were still around here since I just sort of came back around myself. Life sure takes us in strange directions and never thought I'd get so far away from what I had been doing.

So what are you doing full time now? Hope what ever it is, it's been treating you well...
 
SX828POWER said:
n terms of crossovers, I was just going to use a 250hz low pass for the woofer, and then a two way crossover for the mid and highs with a restricting capacitor to the super-tweeter. This would make the speakers bi-ampable for the best flexibility. I did all of the research to ensure that the impedances of the drives would match, so that the crossover frequencies would not change and would be dead on.
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As vinyldavid alluded, there's a little more to it. There is a nominal driver impedance, but that's only marginally helpful when designing a crossover. What you'll need is the actual impedance of the driver at the crossover frequency. Even using that, there's a chance that your filters could have an undesirable phase relationship at or near the crossover frequency. These are issues that don't come up when plugging nominal driver impedances into a crossover calculator - and part of the reason that crossover design is such a huge part of speaker design.

Here's a copy of a recent JBL 3-way crossover, take a look at the UHF section, that's the tweeter. It's charge coupled, so that's an added bit of stuff you can do away with, but if it was as simple as just placing a capacitor in line, don't you think they would have just done that?

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Here's an article by Troels Gravesen, describing three different tweeter crossovers. Notice how none of them are just a capacitor? Also, he includes the phase angle in his plots, to give an idea how that figures into his filters.

http://www.troelsgravesen.dk/95009700.htm

And that's just the tweeter.

I don't want to dissuade you from your quest, but you started out wanting to replicate some iconic large studio monitors. They are iconic not just because of how they look, but because of how they sound. Much of how they sound is down to the crossover circuits used, and even on the iconic old studio monitors, it was much more involved than a single capacitor. Here's a 4343 crossover, for instance:

3143.jpg
 
The 3143 crossover is sophisticated, but basically straight forward with dividing attenuation circuits 18 db/octave roll off filters with additional shelving circuits. But the K2 crossover is a real piece of work with additional impedance correction and protection circuits. There is no way an individual can compete with that kind of design expertise. The amount of money needed for test gear, sound lab and hours and hours for testing would be over whelming for an individual. But I guess if Paul Klipsch and James Lansing could do it any one can.
 
Everyone here is offering up good points. Trying to produce a complete large JBL is probably not a practical venture to get into. However there are lots of JBL cabs out there in sorry shape but with drivers still in them. I saw a Paragon the other day that was left sitting for years in an old barn! You can imagine the water damage, and yet the drivers were there. There are also many people with the skill level who are building their own JBL cabs and creating their own replicas. I don't think many are doing that with speakers other than JBL. Maybe some, but not that many which speaks to the popularity of JBL. How many would like to do that but lack the shop/tools and or skill level? The fact is that as Harman Kardon continues to erode JBL, the vintage lines are gaining more and more popularity. The fact that the JBL of today is likely dying, could make replica cabs from the glory years even more in demand.

JBL professional line has been a serious workhorse in night clubs, strip clubs, practically any venue where good sounding loud music was needed, that you can imagine! And many have had a very rough life, through neglect, bullet holes, what have you, and probably a lot of these old cabinets have fallen in disrepair. Fortunately JBL's were built like tanks so while the drivers may need work, often they are salvageable. Now that JBL's prices have skyrocketed on eBay and CL it seems like there could be a niche spot for some sort of business like yours to make a go. IF you just stick to the cabinets only.

The next hurdle after building a quality replica cabinet is shipment. What you DO NOT want to do is limit your business to just your local area. But look at all those ebay JBL listings. Most say "local pickup only" cuz shipping a complete pair of speakers is cost prohibitive, no matter their value. Here is where my idea of building exact replica JBL cabs, but disassembled so they can sit flat, and in more than one package comes in. Now they still are going to be heavy, but not near AS heavy as a completed JBL, with heavy drivers and pallets and crates etc. But just as important as less weight, is the volume issue. By shipping disassembled you have taken most of that volume away, and now you can ship them countrywide, if not worldwide! Think of all those JBL's sitting out there in partial ruin because the cabinets got wet, or otherwise not repairable. Now that you have given them an option they can take the drivers out, have them rebuilt and put into one of your brand new cabs for a fraction of the price of a Kenrick. I think it could just work! :thumbsup: But not if you try to do the whole thing yourself. Leave that to Kenrick. There is too much going against you to do a complete package. Shipping, rebuilding drivers and crossovers, and definitely not generic components either. Those would definitely bomb.
 
twiiii said:
The 3143 crossover is sophisticated, but basically straight forward with dividing attenuation circuits 18 db/octave roll off filters with additional shelving circuits.
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And as you say, that's a straight forward design. But it's still pretty far removed from a single capacitor. And 18db - how's the phase gonna incorporate with the mid below it? That's something our crossover designer will need to look into.
 
I know nothing about JBL, I'm an Altec guy and we can still buy brand new after market Altec drivers, built from the original Altec tooling, and made by Great Plains Audio. So, I take it that vintage JBL drivers are no longer available new and you have to scrounge for used gear on that one site, are there any modern JBL drivers that could be substituted, have a similar sound signature and still make it a "Jimbo Lancing" equivalent? (How's that for a trade mark evading name for your company?) :)
 
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